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Background: The use of the vancomycin wrap to pretreat the hamstring graft in anterior cruciate ligament reconstruction (ACLR) has grown in popularity since it was first described in 2012 and has significantly reduced rates of postoperative infection. However, it remains unknown if this antibiotic treatment affects the molecular composition of the graft. Purpose: To establish whether treatment with vancomycin at 5 mg/mL, the most commonly used concentration, alters the molecular function of the hamstring graft in ACLR. Study Design: Controlled laboratory study. Methods: Surplus hamstring tendon collected after routine ACLR surgery was used for in vitro cell culture and ex vivo tissue experiments. Vancomycin was used at 5 mg/mL in RPMI or saline diluent to treat cells and tendon tissue, respectively, with diluent control conditions. Cell viability at 30, 60, and 120 minutes was assessed via colorimetric viability assay. Tendon cells treated with control and experimental conditions for 1 hour was evaluated using semiquantitative reverse transcription analysis, immunohistochemistry staining, and protein quantitation via enzyme-linked immunosorbent assay for changes in apoptotic, matrix, and inflammatory gene and protein expression. Results: Vancomycin treatment at 5 mg/mL significantly reduced tenocyte viability in vitro after 60 minutes of treatment ( P < .05); however, this was not sustained at 120 minutes. Vancomycin-treated tendon tissue showed no significant increase in apoptotic gene expression, or apoptotic protein levels in tissue or supernatant, ex vivo. Vancomycin was associated with a reduction in inflammatory proteins from treated tendon supernatants (IL-6; P < .05). Conclusion: Vancomycin did not significantly alter the molecular structure of the hamstring graft. Reductions in matrix protein and inflammatory cytokine release point to a potential beneficial effect of vancomycin in generating a homeostatic environment. Clinical Relevance: Vancomycin ACL wrap does not alter the molecular structure of the ACL hamstring graft and may improve graft integrity.

Several laboratory experiments have demonstrated degradation of carbon tetrachloride (CT) in groundwater, but there appear to have been no corroborating long-term field studies. Investigations conducted in 1989 and 1999 at an industrial site constructed on an infilled estuarine environment in France provide data over a decade for which CT degradation could be evaluated. A Dense Non-Aqueous Phase Liquid (DNAPL) containing oil and >90% CT that was present in 1989 was absent in the extremely reducing site groundwater in both 1999 and 2000 (average Eh=−170 mV at pH 7, sulfide up to 21 mg l −1 , and Fe +2 up to 3.2 mg l −1 ). These conditions facilitated dechlorination of CT to chloroform (CF) present at up to 46 mg l −1 , and methylene chloride (up to 75 mg l −1 ). Carbon disulfide (CS 2 ), a terminal degradation product in reducing environments in laboratory experiments, was present at a mass ratio averaging 2.4:1 CF:CS 2 , indicative of abiotic degradation. The lack of detection of the separate phase CT, the ratio of CF:CS 2 , the presence of low molecular weight organic acids (i.e., acetate ∼900 mg l −1 ; citrate 360 mg l −1 ; and propionate, up to 111 mg l −1 ) and pyrite in conjunction with excess inorganic Cl in groundwater are all indicators of ongoing degradation of the chlorinated compounds. However, while natural attenuation of chloromethanes may be a viable adjunct to strategies designed to remediate CT in reducing groundwater, its efficacy is hard to quantify in complex field environments where upgradient sources are still present.

Background:The medial patellofemoral ligament (MPFL) is the main restraining force against lateral patellar displacement. It is disrupted after patellar subluxation or dislocation. Reconstruction of the MPFL is frequently performed when nonoperative management fails and the patient experiences recurrent patellar dislocation.Purpose:To determine the relationship between the degree of trochlear dysplasia and femoral tunnel position and outcome after MPFL reconstruction.Study Design:Case series; Level of evidence, 4.Methods:A total of 68 patients (72 knees) with recurrent dislocation of the patella underwent MPFL reconstruction. The mean follow-up was 31.3 months (range, 13-72 months). Clinical and functional outcomes were recorded using the Kujala, Lysholm, and Tegner scores. Postoperative complications, participation in sporting activity, and overall patient satisfaction were determined. Radiographs were analyzed to evaluate congruence angle, lateral patellofemoral angle, patellar height, trochlear dysplasia, trochlear boss height, and position of the femoral tunnel.Results:The mean Kujala, Lysholm, and Tegner scores postoperatively were 76.2, 73.8, and 3.6, respectively (n = 61). The mean congruence angle (n = 30) improved from 22.5° to 1.0° postoperatively ( P = .000038), the lateral patellofemoral angle (n = 30) improved from 7.4° to 7.8° postoperatively ( P = .048), and the patellar height (n = 46) using the Caton-Deschamps method improved from 1.1 to 1.0 postoperatively ( P = .000016). Mild trochlear dysplasia grade A/B was found in 89% of patients (n = 54), and 11% of patients (n = 7) had severe grade C/D dysplasia. The mean distance from the anatomic insertion of the MPFL to the center of the tunnel was 9.3 mm (range, 0.5-28.2 mm), with 71.7% thought to be within 10 mm of the anatomic position defined by Schottle (n = 46). When patients with high-grade trochlear dysplasia were excluded, anatomically placed femoral tunnels demonstrated significantly better clinical scores than did tunnels not placed anatomically (Kujala score, P = .028; Lysholm score, P = .012). A multivariate logistic regression analysis also demonstrated that the distance of the femoral tunnel from the anatomic position predicted clinical outcome (Kujala score, P = .043; Lysholm score, P = .028). All of the patients with severe trochlear dysplasia (n = 7) suffered from recurrent dislocations postoperatively, compared with only 9.3% of patients (n = 5) with mild trochlear dysplasia ( P = .0001). Four patients had patellar fractures postoperatively. Of patients with mild dysplasia, 83% were either very satisfied or satisfied with the outcome of their surgery compared with only 57% with severe dysplasia ( P = .05). Of patients with mild trochlear dysplasia, 56% returned to sport postoperatively compared with only 43% of patients with severe trochlear dysplasia ( P = .526).Conclusion:This study demonstrates the importance of restoration of the anatomic insertion point of the MPFL when performing MPFL reconstruction and proposes that this procedure should not be performed in isolation in patients with high-grade trochlear dysplasia.

Summary Successful arthrodesis of the first metatarsophalangeal joint is dependent upon bony union in satisfactory alignment. However, some procedures can be complicated by symptoms related to the metalwork. We assessed the outcome of first metatarsophalangeal joint fusion using a low profile vitallium plate technique with particular respect to metalwork symptoms. First metatarsophalangeal joint arthrodesis was performed using ‘Coughlin' spherical reamers, interfragmentary screw fixation and a dorsal low profile vitallium plate. Twenty-seven patients underwent 33 first metatarsophalangeal joint arthrodeses. Patients were scored by a pre and postoperative foot score and by a postoperative linear scoring system. The mean foot scores were 48.2 preoperatively and 88.0 postoperatively. The mean linear score was + 69.8. Thirty-two of the joints successfully fused with a mean fusion time of 7.59 weeks. One patient had an infected non-union. One patient had undiagnosed foot pain that remained following metalwork removal. No symptoms were directly attributable to the metalwork. Both the scoring systems showed improvements in the postoperative condition of the patient with regards to both functional ability and pain relief. We propose that this method of fixation allows a high fusion rate with a low incidence of complications, particularly those related to the metalwork.

Summary Ten abnormal joints between the medial malleolus and the tarsal navicular were found in six patients with treated idiopathic congenital talipes equinovarus (CTEV). Four cases were bilateral and two cases unilateral. Seven feet had significant reduction or obliteration of the normal angle between the neck and body of the talus and the navicular was subluxed medially. Four of the feet also showed dorsal subluxation of the navicular. Five abnormal joints were degenerate. Interestingly, the other tarsal joints did not show degenerative changes. Magnetic resonance imaging scans performed in five joints confirmed the pseudoarticulation. Five of the feet were symptomatic with ongoing pain at the site of the abnormal joint, four of which were degenerate. Duration of the pain was between 24 and 60 months (mean 36 months). The patients experienced complete, although temporary, relief of pain after a local steroid injection into the abnormal joint. Excision of the abnormal joint in two patients improved their pain to a satisfactory level.

Between February 1982 and December 1985, 133 knees in 107 patients were replaced with a cemented Johnson-Elloy (Accord) total knee arthroplasty. Thirty-five knees were lost during the follow-up period because of death in 29, revision in 3, infection in 1, and refusal of follow-up evaluation in 2. The results of the remaining 98 knees in 76 patients with a 5-8 year follow-up period are presented. The procedure was carried out in all cases presenting for surgery, irrespective of pathology and degree of deformity. The range of flexion achieved as a mean of 93.5 degrees in the osteoarthritic group and 100 degrees in the rheumatoid arthritic group. Eighty-seven percent of the osteoarthritic group and 95% of the rheumatoid arthritic group achieved between 10 degrees and 50 degrees of rotation at 90 degrees of flexion, which was maintained for the duration of the study. Adequate stability in both groups, valgus-varus and rotation in extension, and anteroposterior in flexion was achieved. Survivorship was 97.7% at 80 months.

Enclosures made of plastic sheeting or tubing and large plastic bags placed in aquatic environments have been used to evaluate the efficacy and safety of aquatic pest control agents under actual field conditions. These methods provide for biological replications of field plots and direct comparison of treatment rates and application methods, formulations, timing, and so on. Both efficacy and safety can also be compared by "before" and "after" measurements with positive controls and the option of using both the natural community of the ecosystem and simulated populations introduced in cages or directly to the enclosures. Although plastic bags or cylinders have size limitations, the plastic sheeting can be used to form enclosures of almost any dimension. Results of two field tests are presented to demonstrate the utility of on-site bioassays for determining the concentrations of rotenone needed to eliminate grass carp (Ctenopharyngodon idellus) in ponds and of an experimental piscicide to achieve selective removal of carp (Cyprinus carpio) from a pond containing populations of game fish.

The use of plastic wading pools to simulate lentic environments expedites testing of fish control agents and other pesticides. This method permits replication of a variety of water conditions and benthic substrates and facilitates multiple-parameter testing under biological, physical, and chemical conditions comparable to those in different geographic areas. Similarly, a series of "raceways" or troughs arranged with various substrates can be used to simulate lotic environments complete with pool and riffle ecotypes. Water velocity, temperature, chemistry, and biota can be conveniently controlled to evaluate fish control agents, detoxification rates, and effects on both target and nontarget organisms.

This paper presents the design of a unifying infrastructure for clinical decision support systems (CDSSs) and medical data relating to the perinatal life cycle. The diverse CDSSs designed for deployment within the perinatal life cycle to improve care, such as Artificial Neural Networks and Case-Based Reasoners, are integrated using the eXtended Markup Language (XML) and are subsequently offered as a secure web service. These web services are accessible from anywhere within the hospital information system and from remote authorized sites. The goal of such an infrastructure is to provide integrated CDSS processing in a complex distributed environment, in order to support real-time physician decision-making. This design provides a novel web services infrastructure implementation and offers a strong case study for deploying and evaluating the web services paradigm within a health care environment.

A reengineered approach to the early prediction of preterm birth is presented as a complimentary technique to the current procedure of using costly and invasive clinical testing on high-risk maternal populations. Artificial neural networks (ANNs) are employed as a screening tool for preterm birth on a heterogeneous maternal population; risk estimations use obstetrical variables available to physicians before 23 weeks gestation. The objective was to assess if ANNs have a potential use in obstetrical outcome estimations in low-risk maternal populations. The back-propagation feedforward ANN was trained and tested on cases with eight input variables describing the patient's obstetrical history; the output variables were: 1) preterm birth; 2) high-risk preterm birth; and 3) a refined high-risk preterm birth outcome excluding all cases where resuscitation was delivered in the form of free flow oxygen. Artificial training sets were created to increase the distribution of the underrepresented class to 20%. Training on the refined high-risk preterm birth model increased the network's sensitivity to 54.8%, compared to just over 20% for the nonartificially distributed preterm birth model.

This work extends the functionality of our earlier XML-based health care framework for integrating clinical decision support systems (CDSSs) with capabilities for defining, detecting, and generating clinical alerts in the neonatal intensive care unit (NICU). A first step in this work involved creating a complete NICU XML schema for defining and constraining medical device data, CDSS inputs and outputs, and clinical alerts. The alerts are customizable through a flexible user interface that automatically creates XML documents based on the physician's input specifications. XML documents are transmitted to a central Java application for alert display and transmission. Transmitting XML-based alerts allows the alert information to be shareable in many contexts- within and between hospital information systems, and from remote locations. This is particularly useful when one considers the possibility of offering CDSS-generated alerting systems as ubiquitous web services to pre-authorized users.

The functional ranges of movement of the knee were investigated in a group of patients with knee osteoarthritis (n = 42, mean age 70 years) before, 4 months and at 18-24 months after total knee arthroplasty and then compared with age matched normal subjects (n = 20, mean age 67 years). Flexible electrogoniometry was used to record the maximum flexion-extension angle, the minimum flexion-extension angle and flexion-extension excursions of both knees during eleven functional activities along with the active and passive knee joint range of motion measured using a manual goniometer. Over the eleven functional activities the patients pre-operatively exhibited 28% less knee joint excursion than normal age matched subjects. By 18-24 months following total knee arthroplasty only 2% of this deficit was recovered. Statistically this recovery was only significant in level walking, slope ascent and slope descent. A greater range of movement was measured in a non-weight bearing position than was used in weight bearing functional activity. It is concluded that total knee arthroplasty gives rise to little improvement in knee motion during functional activities and that functional range of movement of the knee remains limited when compared to normal knee function for a minimum of 18 months following operation.

Acute epiglottitis refers to an acute infectious inflammation of the epiglottis usually associated with infection of the immediately adjacent supraglottic structures. It is a wellrecognized cause of catastrophic upper airway obstruction in children and adu1ts.l Haemophilus influenzae type B is widely accepted as being the most common etiologic agent giving rise to epiglottitis in all age groups.2-4 Since the introduction of conjugated vaccines against H influenzae type B, there has been a sharp decline in the incidence of invasive diseases caused by this organism in children, including epiglottitis.5-7 Epiglottitis has been recognized as an important, uncommon treatable cause of potentially fatal upper airway obstruction that can occur at almost any age. Cases before I month of age are quite rare. The earliest cases reported in the English literature include a case of a 5-day-old baby boy with

Cultures of 11 day old chick embryo pectoral muscle were used to study the effects of direct electrical stimulation and neurochemicals such as acetylcholine, acetyl-β-methylcholine, tetrodotoxin, and d-tubocurarine on the acetylcholinesterase levels of muscle. The results suggest that excitation-contraction is an important factor in regulation of muscle acetylcholinesterase. Tetrodotoxin, acetylcholine and its analog acetyl-β-methylcholine increased acetylcholinesterase levels and reduced spontaneous contractions, d-tubocurarine blocked the increase in acetylcholinesterase and the decrease in spontaneous contractions caused by acetyl-β)-methylcholine. Electrical stimulation decreased acetylcholinesterase and increased muscle contractions in normal and in diisopropylfluorophosphate treated cultures. Tetrodotoxin also affected the morphology of the muscle cells, as if it adversely affected normal growth and differentiation. Electrical stimulation did not increase muscle creatine kinase.

Action potentials (APs) mediated by calcium ions have been recorded intracellularly from neurons in cell cultures prepared from fetal mouse hippocampus and examined between 18 h and 46 days in culture. These APs occurred in media containing sodium ions (4–14 mM), calcium ions (5–8 mM), and tetrodotoxin (1 μg/ml), were enhanced by tetraethylammonium ions (5–20 mM), and were blocked by cobalt ions (10 mM). In cultures prepared from 18-day fetuses, the incidence of neurons with calcium AP activity was 46% (n = 35) from 18 h to 2 days. For the next 6 weeks in culture the incidence was between 83 and 89%. The lower incidence of calcium APs is due to temporary loss of calcium AP capability immediately following culture preparation, rather than a lack of development of this property by fetal day 18, because cultures of neurons chronologically equivalent to fetal ages 16–18 days have a high incidence of calcium APs (91%, n = 22). Sodium-dependent APs can be demonstrated in cells which have calcium APs by perfusion techniques. These dual AP mechanisms persist within the same cell throughout the time span of the cultures in this study. Special features of calcium APs in cultured hippocampal neurons included the following: (1) calcium APs were optimally generated when the membrane potential was depolarized to −40 mV except with tetraethylammonium ions in the medium. Under this condition, optimal activity occurred between −60 and −70 mV; (2) AP morphology suggested the presence of multiple generator sites and the distribution of calcium channels over both soma and processes; (3) hyperpolarizing afterpotentials were well developed in some, but not all cells with calcium APs; (4) up to 25% of the cells in selected cultures exhibited rhythmic pacemaker activity with a frequency which increased linearly from about 1 to 7 Hz with increasing steady current injection; (5) manganese ions did not effectively block calcium APs in cultured hippocampal neurons and, in fact, appeared to support AP activity. Marked hyperpolarizing afterpotentials followed some manganese APs.

Primary cultures of dissociated hippocampi from fetal mice were examined for the presence of binding sites for [3H]diazepam. The binding assays were done with living cells still attached to the culture dish. The cells contain high affinity binding sites for [3H]diazepam, Kd = 5 nM, which are completely inhibited with 20 nM R05-4864 but only 26% with 20 nM lorazepam. The binding was inhibited by purinergic compounds and by quinidine. The living cell did not exhibit increased binding of [3H]diazepam in the presence of GABA and in fact a slight decrease in binding was found. This was also found when live, intact C6 glial cells were investigated. These observations suggest that the use of living cells to study the benzodiazepine receptor is valuable and maybe necessary to fully characterize this receptor.

Previous studies have established that short treatments with diisopropylphosphorofluoridate of chick embryo muscle cultures irreversibly inhibit the enzyme acetylcholinesterase and that the enzyme's levels in the cells rapidly recover due to synthesis of new protein. In addition, it has been shown that acetylcholine, acetyl-β-methylcholine and choline increase the acetylcholinesterase content of the cultures. In the experiments presented here, actinomycin D and cycloheximide were used to study the relationships between the synthesis of ribonucleic acid and of protein, the recovery of acetylcholinesterase levels after diisopropylphosphorofluoridate treatment and the increase of acetylcholinesterase levels evoked by choline and its esters. Both recovery of acetylcholinesterase and the increase in its activity with acetyl-β-methylcholine occurred in the absence of ribonucleic acid synthesis but required protein synthesis. The results suggest that transcription of desoxyribonucleic acid and a change in the degradation rate of acetylcholinesterase are not involved. An additional finding was that the level of newly synthesized acetylcholinesterase activity continued to increase for a short period of time after synthesis of protein had ceased, as if some previously synthesized protein was being transformed into active enzyme.

A method is described for the determination of 14 elements (Al, Cd, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Ni, K, Na, Zn) in uranium and uranium compounds by atomic absorption spectroscopy. A sample is dissolved in 6–8 N nitric acid, from which the uranium is selectively removed by a single extraction with tributyl phos phate. The aqueous layer is evaporated to dryness and the residue is re-dissolved in 0.2 N hydrochloric acid. Any or all of the elements can then be determined in the solution by atomic absorption spectroscopy. The limits of error in the analyses are less than 10%. Thus, the method gives about the same precision as colorimetric procedures, and it is much more precise than emission spectroscopy.

Rapid methods have been developed for the direct measurement of cobalt and copper in various alloys. These spectrophotometric methods are based on measurement of the intensely colored complexes formed by cobalt and copper ions in an acetone-hydrochloric acid medium, at 628 and 400 nm, respectively. The cobalt method is highly selective; cobalt can be determined without interference from large quantities of iron, chromium, nickel, vanadium, molybdenum, and copper. In the determination of copper, only large quantities of iron, molybdenum, or vanadium interfere, but their interferences can be easily eliminated by a rapid solvent extraction procedure. The methods are sufficiently sensitive to determine 0.015% cobalt and 0.005% copper in aluminum alloys. Both elements can be determined with a limit of error of 1.2–1.3% at the 95% confidence interval.

The application of atomic absorption to the microdetermination of antimony, iron, and molybdenum in nickel and uranium is described. These elements are separated and concentrated by a single solvent extraction from 8N hydrochloric acid into n-amyl acetate. The extract is then analyzed directly by atomic absorption techniques. For the 95% confidence interval, the limits of error per analysis at the 1-p.p.m. level are ±4, ±10 and ±6% for antimony, iron, and molybdenum, respectively. In general, the described procedure is more rapid and yields more accurate results than colorimetric procedures for these elements. Since the amyl acetate-hydrochloric acid solvent extraction system can separate antimony, iron, and molybdenum from gross quantities of nickel or uranium (i.e. up to 25 g), the method is capable of detecting the elements at about 0.05 μ g .

A rapid and accurate method has been developed for the determination of uranium in complex solutions produced in the recovery of uranium from nuclear fuels. These solutions usually contain 0.1–20 g U l-1 and high concentrations of aluminum nitrate in addition to a variety of cations and anions associated with fuel-element constituents and dissolution media. The method involves the solvent extraction of uranium from an acid-deficient aluminum nitrate-tetrapropylammonium nitrate solution into 2% tributy1 phosphate in n-amy1 acetate. The uranium is then backextracted with a concentrated phosphoric acid solution, and titrated by the method of Davies and Gray. The uranium extraction efficiency for sample solutions weighing up to 50 g is 99.9% or better, and the limit of error per analysis with 95% confidence is ±0.6%. No prior sample preparation is necessary, no expensive equipment is required, and even unskilled personnel can do duplicate analyses in 1.5 h.

A study of the factors which affect the gravimetric determination of uranium in uranyl nitrate is described. In the gravimetry of uranium, the U3O8 (weighing form) produced by ignition is usually assumed to deviate

The GABA uptake mechanism has been characterized in hippocampal cell cultures prepared from fetal mice of 13-19 days gestational age [3H]GABA is accumulated selectively by neuronal cells by a high-affinity (Km = 3 micro M) mechanism that is an early property of the neurons. Autoradiography of [3H]GABA uptake revealed that approximately 30% of the neuronal cells had uptake. A unique small neuronal type did not have [3H]GABA uptake but was found to have [3H]glutamic acid uptake, suggesting that these neurons may be granule cells. The selective labeling of neurons with [3H]GABA and [3H]glutamic acid is consistent with the idea that high-affinity uptake of a transmitter may be unique to neurons that use that transmitter.